In contrast to spark plugs with swirl chambers, in which the ground electrodes or ground electrode supports are arranged on the wall of the swirl chamber so that the current flowing during ignition is dissipated by the ground electrode through the wall of the swirl chamber to the spark plug body, such as are known from EP 1,265,329 A1, for example, the spark plugs of the present type have the advantage that the ground electrodes and their supports represent a system independent of the wall of the swirl chamber on account of the arms of the ground electrode support that extend within the swirl chamber. This ensures a defined and uniform carrying of current through the ground electrode support without any dissipation of current through the wall of the swirl chamber. Moreover, simple adjustment of the ground electrodes is made possible so that a spark gap that has changed due to electrode consumption resulting from use can be corrected. With regard to thermal considerations, the dissipation of heat from the ground electrodes through the arms of the ground electrode support, which are shielded from the wall of the swirl chamber, is better than when the ground electrodes are attached to the swirl chamber wall. These distinctions are addressed in EP 2,208,268 B1 and WO2012/113002 A1.
An object of the present invention is to further improve a spark plug of the type mentioned at the outset while preserving the stated advantages.